The office of the Attorney General was established by the Judiciary Act of 1789 as a part-time job for one person, but grew with the bureaucracy. At one time, the Attorney General gave legal advice to the U.S. Congress as well as the President, but in 1819 the Attorney General began advising Congress alone to ensure a manageable workload.[6] Until March 3, 1853, the salary of the Attorney General was set by statute at less than the amount paid to other Cabinet members. Early Attorneys General supplemented their salaries by running private law practices, often arguing cases before the courts as attorneys for paying litigants.[7]

Following unsuccessful efforts (in 1830 and 1846) to make Attorney General a full-time job,[8] in 1869, the U.S. House Committee on the Judiciary, led by Congressman William Lawrence, conducted an inquiry into the creation of a "law department" headed by the Attorney General and also composed of the various department solicitors and United States attorneys. On February 19, 1868, Lawrence introduced a bill in Congress to create the Department of Justice. President Ulysses S. Grant signed the bill into law on June 22, 1870.[9]

Grant appointed Amos T. Akerman as Attorney General and Benjamin H. Bristow as America's first Solicitor General the same week that Congress created the Department of Justice. The Department's immediate function was to preserve civil rights. It set about fighting against domestic terrorist groups who had been using both violence and litigation to oppose the 13th, 14th, and 15th Amendments to the Constitution.[10]

Both Akerman and Bristow used the Department of Justice to vigorously prosecute Ku Klux Klan members in the early 1870s. In the first few years of Grant's first term in office there were 1000 indictments against Klan members with over 550 convictions from the Department of Justice. By 1871, there were 3000 indictments and 600 convictions with most only serving brief sentences while the ringleaders were imprisoned for up to five years in the federal penitentiary in Albany, New York. The result was a dramatic decrease in violence in the South. Akerman gave credit to Grant and told a friend that no one was "better" or "stronger" than Grant when it came to prosecuting terrorists.[11]George H. Williams, who succeeded Akerman in December 1871, continued to prosecute the Klan throughout 1872 until the spring of 1873 during Grant's second term in office.[12] Williams then placed a moratorium on Klan prosecutions partially because the Justice Department, inundated by cases involving the Klan, did not have the manpower to continue prosecutions.[12]

The "Act to Establish the Department of Justice" drastically increased the Attorney General's responsibilities to include the supervision of all United States Attorneys, formerly under the Department of the Interior, the prosecution of all federal crimes, and the representation of the United States in all court actions, barring the use of private attorneys by the federal government.[13] The law also created the office of Solicitor General to supervise and conduct government litigation in the Supreme Court of the United States.[14]

In 1933, President Franklin D. Roosevelt issued an executive order which gave the Department of Justice responsibility for the "functions of prosecuting in the courts of the United States claims and demands by, and offsenses [sic] against, the Government of the United States, and of defending claims and demands against the Government, and of supervising the work of United States attorneys, marshals, and clerks in connection therewith, now exercised by any agency or officer..."[17]

The U.S. Department of Justice building was completed in 1935 from a design by Milton Bennett Medary. Upon Medary's death in 1929, the other partners of his Philadelphia firm Zantzinger, Borie and Medary took over the project. On a lot bordered by Constitution and Pennsylvania Avenues and Ninth and Tenth Streets, Northwest, it holds over 1,000,000 square feet (93,000 m2) of space. The sculptor C. Paul Jennewein served as overall design consultant for the entire building, contributing more than 50 separate sculptural elements inside and outside.[citation needed]

Various efforts, none entirely successful, have been made to determine the original intended meaning of the Latin motto appearing on the Department of Justice seal, Qui Pro Domina Justitia Sequitur (literally "Who For Lady Justice Strives"). It is not even known exactly when the original version of the DOJ seal itself was adopted, or when the motto first appeared on the seal. The most authoritative opinion of the DOJ suggests that the motto refers to the Attorney General (and thus, by extension, to the Department of Justice) "who prosecutes on behalf of justice (or the Lady Justice)".[18]

The motto's conception of the prosecutor (or government attorney) as being the servant of justice itself finds concrete expression in a similarly-ordered English-language inscription ("THE UNITED STATES WINS ITS POINT WHENEVER JUSTICE IS DONE ITS CITIZENS IN THE COURTS") in the above-door paneling in the ceremonial rotunda anteroom just outside the Attorney General's office in the Department of Justice Main Building in Washington, D.C.[19] The building was renamed in honor of former Attorney General Robert F. Kennedy in 2001. It is sometimes referred to as "Main Justice".[20]

Federal Bureau of Prisons (BOP) – the Three Prisons Act of 1891 created the federal prison system. Congress created the Federal Bureau of Prisons in 1930 by Pub. L. No. 71–218, 46 Stat. 325, signed into law by President Hoover on May 14, 1930.[34][35][36]

Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) – Except for a brief period during Prohibition, ATF's predecessor bureaus were part of the Department of the Treasury for more than two hundred years.[37] ATF was first established by Department of Treasury Order No. 221, effective July 1, 1972; this order "transferred the functions, powers, and duties arising under laws relating to alcohol, tobacco, firearms, and explosives from the Internal Revenue Service to ATF.[38] In 2003, under the terms of the Homeland Security Act, ATF was split into two agencies – the new Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) was transferred to the Department of Justice, while the Alcohol and Tobacco Tax and Trade Bureau (TTB) was retained by the Department of the Treasury.[37]

In 2003, the Department of Justice created LifeAndLiberty.gov, a website that supported the USA PATRIOT Act. It was criticized by government watchdog groups for its alleged violation of U.S. Code Title 18 Section 1913, which forbids money appropriated by Congress to be used to lobby in favor of any law, actual or proposed.[40] The website has since been taken offline.